A typical labor process during childbirth is divided into three stages. The first and second stages are directly involved in the delivery of the child, and the third stage involves the delivery of the placenta. The first stage of labor begins with the onset of rhythmic uterine contractions and ends with complete cervical dilatation. The second stage of labor begins upon complete cervical dilatation and ends after the birth of the child. The third stage of labor extends from the birth of the child to the complete delivery of the placenta. The labor progress, especially through the second stage of labor, is driven by two types of labor forces. The primary force is produced by the involuntary contractions of the mother's uterus (i.e., uterine muscle contractions). The secondary force is produced by the increase of intra-abdominal pressure created by voluntary contractions of the mother's abdominal muscles, including pelvic musculatures and diaphragm. These forces act synergistically to increase the intrauterine pressure and aid the expulsion of the child from the uterus.
The use of epidurals and pain relieving drugs during the labor and delivery process can desensitize the birthing mother from experiencing the natural body signals needed to push the baby through the birth canal and thereby ultimately delay the progression of childbirth. One indication of this phenomenon is that in recent years, there has been a dramatic increase in the incidence of children born by Cesarean childbirth. This form of child birth significantly increases the cost to the healthcare system when compared to a natural vaginal delivery. In addition, the birthing mother needs significantly more time to recover from a Cesarean operation compared to a natural vaginal child delivery. Systemic analgesic drugs, epidural anesthesia, and the long duration of exhaustive labor all can lead to the weakening of the secondary force, and sequentially to delayed labor duration or even dystocia (arrest of labor). Thus, in some instances, the duration of the second stage of labor is prolonged by ineffective or inadequate pushing by the mother, which can lead to injuries of the pelvic floor, fetal distress, higher rate of infant mortality, neonatal seizures, postpartum hemorrhage, and/or to delivery by Cesarean section.
While prior apparatus and methods like those disclosed in U.S. Patent Application Publications 2007/0031466 and U.S. Pat. No. 7,673,633 provide stable support for the soft perianal tissues near the anal orifice, these can be further improved to provide additional benefits for labor management to increase intrauterine pressure (e.g., by strengthening contractions and pushing), thereby decreasing the duration of the second stage of labor and/or decreasing the incidence of Cesarean childbirth. More specifically, there exists a need for devices that permit a healthcare provider to actively and intermittently monitor and guide the labor process to promote more effective fetal descent, thereby decreasing the duration of the second stage of labor and increasing the likelihood of successful vaginal births.
The devices and methods described herein overcome one or more deficiencies of the prior art.